1. Field of the Invention
The present invention relates to an endoscopic device, and more particularly to an endoscopic device that alternately inserts an insertion portion of an endoscope and an insertion aid member to insert the insertion portion into an alimentary canal in a deep part such as small intestine or large intestine for observation.
2. Related Art
When an insertion portion of an endoscope is inserted into an alimentary canal in a deep part such as small intestine, complex bending of intestine prevents a force from being transmitted to a tip of the insertion portion in simple insertion of the insertion portion, and insertion into a deep part is difficult. For example, surplus bending or flection in the insertion portion prevents the insertion portion from being further inserted into the deep part. Thus, a method is proposed for inserting an insertion portion of an endoscope covered with an insertion aid member into a body cavity, and guiding the insertion portion with the insertion aid member to prevent surplus bending or flection of the insertion portion.
Japanese Patent Application Laid-open No. 51-11689 describes an endoscopic device including a first balloon at a tip of an insertion portion of an endoscope, and a second balloon at a tip of an insertion aid member (also referred to as an over tube or a sliding tube). This endoscopic device alternately inserts the insertion portion and the insertion aid member while repeating expansion and contraction of the first balloon and the second balloon, thereby allowing the insertion portion to be inserted into a deep part of intestine with complex bending.